ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
49 
former divided into two groups — that of the Endostylophora, in which 
the pharynx is provided with an endostyle, e.g. Oikopleura and Fritil - 
laria ; and the Polystylophora, in which the pharynx is provided with 
numerous finger-like processes arranged in rows, e. g. Kowalevskia. The 
latter are divided into the Thaliacea, in which the protostigmata are 
undivided and the cloaca posterior. These pelagic forms are either 
Myosomata, e.g. Doliolum, Salpa, Anchinia, or Pyrosomata. The Ascidi- 
acea are divided into three groups : — Stolidobranchia , e.g. Botryllus and 
Goodsirea ; Plilebobranchia , e.g. Perophora and Diazona ; and Aplouso- 
branchia, e. g. Clavelina and Didemnum. 
Notes on Tunicate Morphology.* — Dr. M. M. Metcalf has a note on 
the presence of pharyngeal and cloacal glands in Cynthia partita. Over 
the whole surface of the pharynx and cloaca of this Tunicate there are 
minute pores, which are the openings of the ducts of well -developed 
glands. The author has not, however, yet determined the nature of 
these organs or the character of their secretion. He next discusses some 
points in the anatomy of the nervous system of Boltenia bolteni. In this 
form the nerve runs from the ganglion to the walls of the ciliated funnel, 
and among its fibres there are found scattered ganglion-cells. The 
author was, however, unable to trace the nerve-fibres into actual union 
with individual cells of the ciliated funnel, as this can only be done with 
fresh material, which he was unable to obtain. He does not think that 
the presence of nerve-fibres running to the ciliated funnel proves that 
the organ is sensory, though it does, however, make it possible that it 
may be so. Attention is next drawn to the ganglionated condition of 
certain nerve-cords and their intimate connection with muscle-bundles. 
The nervous nature of certain lateral outgrowths from the ganglion in 
the chain-form of Salpa cordiformis is pointed out, and there are some 
notes upon the smaller eyes in the Salpidse. The author has finally a 
note on the precocious development of the testis, and the absence of the 
elaeoblast in the young chain individuals of Salpa cylindrica. 
Development of Salpa democratica (mucronata).f —Prof. A. Korot- 
neff corroborates Salensky’s account of the early stages. The ovum has 
a long stalk, a cellular follicle, a relatively large nucleus. In a remark- 
able way the oviduct forms around the fertilised ovum a cap or brood- 
sac, with the base of which the follicle fuses. The margins of the 
brood-sac close around the follicle and the segmenting ovum ; the follicle 
cells multiply and a number come to lie between the ovum and the 
follicle wall, penetrating even between the blastomeres. Some of the 
blastomeres remain active and capable of further division ; others are 
dislocated and form nutritive material. The peculiar history of the 
degenerating blastomeres is followed up. Besides the blastomeres 
active and passive and the follicle-cells, other elements, perhaps kalym- 
mocytes, are soon distinguishable ; they penetrate the embryo. 
Korotneff describes the “ placenta,” which does not arise from the 
ectoderm of the embryo, but is wholly maternal. The blood-forming 
bud ( Blut-knospe ) is wholly due to follicle-cells. Two groups of blasto- 
meres are differentiated — a plastic and a gonogenic group. Through an 
opening in the floor of the brood-sac mesenchyme-cells and blastocytes. 
* Anat. Anzeig., xi. (1895) pp. 329-40 (9 figs.). 
t Zeitschr. f. wiss. Zool., lix. (1895) pp. 29-45 (1 pi.). 
1896 
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